Material handling machine



' April 29, 1969 D. F. PRZYBYLSKI 3,441,154

MATERIAL. HANDLING MACHINE Sheei Origin a1 Filed April 4 1966 INVENTOR.DAN/62 l-T PR2 YBYL .SK/

MM TORNEYS D. F. PRZYBYLSKI MATERIAL HANDLING MACHINE A ril 29, 1969Sheet Criginal Filed April 4 FKSZ , INVENTOR. DAN/EL A PRZYBYLSK/ BY WaFIG .4

and power providing a boom stroke United States Patent 3,441,154MATERIAL HANDLING MACHINE Daniel F. Przybylski, Winona, Minn., assignorto The Warner & Swasey Company, Cleveland, Ohio, a corporation of OhioOriginal application Apr. 4, 1966, Ser. No. 540,014,

now Patent No. 3,392,855. Divided and this application Sept. 20, 1967,Ser. No. 670,517

Int. Cl. B65d 71/00, 65/16, 75/12 U.S. Cl. 214-138 9 Claims ABSTRACT OFTHE DISCLOSURE The present application is a divisional of United Statesapplication Ser. No. 540,014, filed Apr. 4, 1966, now Patent No.3,392,855 and assigned to the assignee of the present invention.

The present invention relates to a material handling machine, andparticularly relates to a material handling machine, such as a backhoe,which includes a boom member having a dipper stick pivotally connectedto the end of the boom member, and wherein the boom member is pivotallyconnected to a support for pivotal movement about a horizontal axis andpower means which acts between the boom and the support for effectingvertical pivotal movement of the boom.

Known material handling machines, such as a backhoe, include a boomcarried by a support for pivotal movement in a substantially verticalplane about a horizintal axis. The vertical movement or stroke of theboom about the horizontal pivot axis is effected by a power means. Thepower means moves the boom at a particular speed having a particularspeed-power relationship. Preferably, in known material handlingmachines, the power means includes a hydraulic cylinder and piston rod.The hydraulic cylinder is generally connected for pivotal movement abouta horizontal axis to the support and the outer end of the piston rod isgenerally pivotally connected to the boom so as to provide for thenecessary relative movements between the piston rod and boom, on the onehand, and the hydraulic cylinder and support, on the other hand, as theboom moves vertically about the horizontal pivot axis.

The boom generally carries on its outermost end a dipper stick equippedwith a suitable tool for performing some operation. Commonly, the toolis a bucket for effecting digging or movement of some material. Thesemachines, however, are effective to perform numerous differentoperations, depending upon the use of the tool supported on the end ofthe boom, and may be capable of lifting and/or carrying heavy loads. Dueto the various uses for these machines, the lifting and/0r digging powerrequirements for the boom vary. Moreover, the desired speed of verticalmovement of the boom also varies.

In accordance with the present invention, there is provided a new andimproved material handling machine having a boom carrying a dipper stickand wherein the boom is movable in a vertical plane by a power means andwherein the speed-power relationship for boom movement may be controlledand varied within limits. This 3,441,154 Patented Apr. 29, 1969 providesfor rapid boom movement when handling light loads requiring littlepower, and also provides for handling heavy loads requiring greaterpower but at a low speed. The ability to vary the speed-powerrelationship does provide a material handling machine of greaterversatility and efficiency.

Accordingly, the principal object of the present invention is theprovision of a new and improved material handling machine having a boomcarrying a dipper stick and wherein the boom is pivotal about ahorizontal axis by power means and which is constructed and arranged sothat the speed-power relationship for boom movement may be controlledthrough a wide range whereby the boom may be readily moved eitherthrough a power stroke at a relatively low rate of speed or through aspeed stroke at a relatively high rate of speed but at less power.

A still further object of the present invention is the provision of anew and improved material handling machine incorporating a boomsupported for pivotal movement about a horizontal axis relative to asupport frame and a hydraulic lift mechanism operatively connected toeffect the vertical movement of the boom and wherein the lift cylinderis connected to a link member which, in turn, is pivotally connected tothe boom and wherein a hydraulic cylinder acts between the link andsupport frame and when energized moves the link member so as to vary therelative position of the boom pivot and the connection of the piston rodrelative to the boom thereby varying the effective force applied by thehydraulic mechanism to effect movement of the boom.

Further objects and advantages of the present invention will be apparentto those skilled in the art to which it relates from the followingdetailed description of the preferred embodiment thereof made withreference to the accompanying drawings forming a part of thisspecification and in which:

FIG. 1 is a schematic perspective view of a material handling machineembodying the present invention;

FIG. 2 is a detailed view of a portion of the material handling machineshown in FIG. 1;

FIG. 3 is a view illustrating schematically the machanism shown in FIG.2; and

FIG. 4 is a sectional view taken approximately along section line 4-4 ofFIG. 2.

The present invention provides an improved material handling machinehaving a boom movable in a vertical plane about a substantiallyhorizontal axis and wherein the movement of the boom is effected by apower means. The present invention is adapted for use in any type ofmaterial handling machine which incorporates such a boom and isparticularly adapted for use in material handling machines which havevarying demands with regard to speed of boom movement and powercapability of the boom.

As representing the preferred embodiment of the present invention, FIG.1 illustrates a material handling machine 10. The material handlingmachine 10 includes a support carrier 11 which carries a supportplatform 12. The support platform 12 is rotatable about a substantiallyvertical axis and carries a boom structure 13. The boom srtucture 13 issupported for pivotal movement about a horizontal axis 91 and is pivotedabout the horizontal axis 91 by a power means 93.

The boom structure 13 includes a boom member which is pivotallysupported for movement about the axis 91 by pivot pin means whichextends through a pair of spaced support frame members 92 secured to theplatform 12. Upon actuation of the power means 93, the boom 90 movesrelative to the support platform 12 and support frame members 92. Theboom 90 on its outermost end carries a dipper stick 22 for pivotalmovement relative to the boom 90. The dipper stick 22 may be pivotedabout a pivot axis 23 by a hydraulic cylinder 24. The outermost end ofthe dipper stick 22, of course, carries a suitable material handlingimplement, a digging bucket 26, as shown in the drawings and which issuitably actuated by a hydraulic power means (not shown) in aconventional manner.

The power means 93 for effecting vertical movement of the boom ispreferably a hydraulic power means including a cylinder 94 and a pistonrod 96 pivotally connected at its outer end to the boom 90 at a locationbelow the pivot axis 91 for the boom 90. The piston rod 96 is pivotalrelative to the boom about a pivot axis 97. The piston rod, when itmoves, applies a force to the boom 90 to effect movement thereof.

In accordance with the present invention, the material handling machineis constructed so that the speedpower relationship for boom movement canbe varied. Thus, the boom 90 may be moved at dilferent speeds and havedifferent lifting capabilities. The speeds and power capabilities can bevaried over a substantial range, and at one limit the boom can movethrough a speed stroke wherein the boom moves through a wide range ofmovement at a relatively fast speed, while at the other limit, the boom90 moves through a power stroke wherein the boom moves through a lesserrange of movement than in the speed stroke but is capable of handlinggreater loads.

During the speed stroke, the hydraulic mechanism 93 applies a givenforce to the boom to effect movement thereof about the pivot axis 91,whereas during the power stroke the hydraulic mechanism applies agreater effective force to the boom to effect movement of the boom aboutthe pivot axis 91. In view of the fact that a greater effective force isapplied to the boom for movement about the pivot axis, the boom iscapable of handling greater loads during the power stroke.

The fact that the speed-power relationship for boom movement can bevaried enables the material handling machine 10 to be utilized highlyeffectively and with a great flexibility. The boom is, of course,capable of moving at higher rates of speed through a wider range ofmovement, thereby enabling light loads to be handled relatively quicklyand through a wide range of movement. The fact that the boom is capableof moving through a power stroke enables the mechanism to be utilizedfor digging in relative hard ground and more readily enables thematerial handling machine to be utilized for lifting heavier loads.

More specifically, the piston rod 96 is pivotally connected at 97 to aplate or link member 98 which, in turn, is pivotally connected at 99 tothe boom 90. The link 98 is also pivotally connected at 97 to a pistonrod 101 of a hydraulic cylinder 102. The hydraulic cylinder 102 ispivotally connected to the frame for pivotal movement about an axis 103of a pivot pin 104 and which axis is spaced a slight distance from theboom pivot axis 91. The point 97 at which the lifting force is appliedto the boom is located below the boom axis.

The hydraulic cylinder 102 and the link 98 comprise means for selectingwhether the boom moves through a power stroke or a speed stroke.Specifically, when the cylinder 102 is in its de-energized condition andthe parts are in the position shown schematically in full lines in FIG.3, the boom, when moved about its pivot axis 91 is moved through a speedstroke through an angle of movement designated H in FIG. 3. However,when the cylinder 102 is energized and the link 98 is moved about itspivot 99, the point 97 at which the force is applied by the hydraulicmechanism 93 to the boom is moved away from the boom pivot point 91 anddownwardly to the location designated 97a.

When the point 97 is moved to 97a, a lengthening of the lever arm forthe boom lifting force occurs. The lever arm LS for the speed stroke isconsiderably shorter than the lever arm LP for the power stroke.Moreover,

the angle T which is the angle formed by a line indicating the forceapplied by the mechanism 93 and a line extending through the boom pivotaxis 91 and the point of connection of the hydraulic mechanism 93 to thelink 98 is less than the angle U which is formed between these samelines during the speed stroke and is more nearly Thus, the effectiveforce applied to the boom is substantially greater when the parts are inthe power position. When in this position and the hydraulic mechanism isenergized, the boom moves through a power stroke and through a range ofmovement, designated I in FIG. 3, which is substantially less than therange of movement designated H. Moreover, as shown in FIG. 3, the boompower stroke lies entirely within the range of movement of the speedstroke. Furthermore, the speed-power relationship can be varied withinthese limits so that the intermediate speed-power relationships areavailable by moving link 98 to a position intermediate its limitpositions.

It should be apparent from the above that the preferred embodiment ofthe present invention has been described in considerable detail, butthat certain modifications, changes, and adaptations may be made thereinby those skilled in the art to which it relates.

What is claimed is:

1. A material handling machine comprising boom support means, a boommember carried by said boom support means, a pivotal interconnectionbetween said boom member and said boom support means adjacent one end ofsaid boom member and providing for pivotal movement of said boom memberrelative to said boom support means, power means acting between saidboom member and said boom support means for effecting pivotal movementof said boom member relative to said boom support means, at least onelink member and means supporting said link member on said boom memberbelow the boom pivot axis for movement relative to said boom pivot axis,said power means having a pivotal interconnection with said link membermovable relative to said boom pivot axis upon movement of said linkmember relative to said boom.

2. A material handling machine as defined in claim 1 wherein said meanssupporting said link member on said boom member supports said linkmember for pivotal movement relative to said boom member.

3. A material handling machine as defined in claim 1 further includingadditional power means for moving said link member relative to said boommember and acting between said link member and said support means.

4. A material handling machine as defined in claim 1 wherein said powermeans has a pivotal interconnection with said boom support means and islocated below said pivotal interconnection of said boom member and saidboom support means.

5. A material handling machine comprising boom support means, a boommember carried by said boom support means, a pivotal interconnectionbetween said boom member and said boom support means adjacent one end ofsaid boom member and providing for pivotal movement of said boom memberrelative to said boom support means, power means acting between saidboom member and said boom support means for effecting pivotal movementof said boom member relative to said boom support means, at least onelink member movably supported on said boom member for movement relativeto said boom pivot axis, said power means having a pivotalinterconnection with said link member movable relative to said boompivot axis upon movement of said link member relative to said boom, andadditional power means acting between said boom support means and saidlink member for effecting movement of said link member relative to saidboom member.

6. A material handling machine as defined in claim 5 wherein said meanssupporting said link member on said boom member supports said linkmember for pivotal movement relative to said boom member.

7. A material handling machine comprising a support, a boom carried bysaid support, means supporting said boom for pivotal movement relativeto said support about a boom pivot axis, hydraulic power means actingbetween said boom and said support for selectively effecting pivotalmovement of said boom about said boom pivot axis, said hydraulic powermeans comprising a hydraulic cylinder pivotally connected to saidsupport and a piston rod pivotally associated with said boom at a pointon the boom below said boom pivot axis, and means for selecting a powerstroke or a speed stroke for said boom comprising additional power meansacting on one of said pivotal connections for moving said one of saidpivotal connections from a first position wherein said hydraulic powermeans applies a given elfective force for moving said boom about saidpivot axis and a second position wherein said hydraulic power meansapplies a greater eifective force to said boom for moving said boomabout said pivot axis.

8. A material handling machine as defined in claim 7 wherein said onepivotal interconnection comprises the pivotal interconnection of saidhydraulic power means to said boom, and wherein said piston rod ispivotally connected to a link member pivotally connected to said boom,and said additional power means effects movement of said link member tovary the position of the pivotal interconnection of said piston rod andlink.

9. A material handling machine as defined in claim 8 wherein saidadditional power means comprises a hydraulic cylinder pivotallyconnected to said support adjacent to the boom pivot axis and a pistonrod extending from the cylinder and pivotally connected to said linkmember.

References Cited UNITED STATES PATENTS 3,388,819 6/1968 Przybylski214138 3,392,855 7/1968 Przybylski 214--l38 HUGO O. SCHULZ, PrimaryExaminer.

US. Cl. X.R.

